IID may refer to:

• Interface Identifier, the last 64-bits of an IPv6 address
• Internet identity, a social identity used by Internet users
• Internet Identity, an Internet security company
• Ignition interlock device, a breathalyzer connected to a vehicle's engine
• Independent and identically distributed random variables in probability theory
• Interaural intensity difference in determining the location of a sound
• Internal Investigations Division (in law enforcement)
• IRIX Interactive Desktop, software for interacting with a computer running the IRIX operating system
• Iterative and Incremental Development in software development
• A COM Interface ID
• Invoke Image Display an Integrating the Healthcare Enterprise (IHE) Integration Profile
• Imperial Irrigation District
• Imperial Institute of Design, a design school in Monteswar, West Bengal, India

See also

• 2D (disambiguation), including a list of topics named II-D, etc.

This disambiguation page lists articles associated with the title IID.
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